Rachel Maddow first came on my radar in the spring of 2004, when she, along with Lizz Winstead and Chuck D of Public Enemy hosted an early morning radio show called Unfiltered on the newly minted Air America, an attempt to counter rightwing talk radio with liberal programming.

Radio has this ability to make the listener feel like they share a secret with the hosts and the few, hard-to-know listeners out there. I hoped people tuned in to listen to the hosts trade jokes and talk about politics and music, and mostly I wanted other people to learn about this Maddow character, who brought to every episode a dynamic mix of sparkling good humour, intelligent analysis and a broad view of what issues should matter.

Unfiltered didn't make the first round of reshuffling at Air America, but Maddow hung in, hosting her own eponymous radio show and eventually moving to television, first as a guest pundit and now as a host of her own night time political talkshow on MSNBC.

Before it happened, most American liberals would have never imagined that Maddow could have her own programme on any cable network, much less the same network that had, just a few years before, tried to pull in a rightwing audience by giving hard right nut Michael Savage his own show (before pulling it after he told a gay caller to die from Aids).

It's not just that Maddow is a liberal. After all, MSNBC had already given a spot to liberal commentator Keith Olbermann and his frequent, angry rants. It was mostly hard to imagine a cable news network rewarding a pundit for being sober-minded and nuanced in her analysis, as well as suspicion that homophobia would prevent it from promoting a lesbian who favours a more masculine way of dressing.

But 2008 was a year for re-arranging American expectations about who gets to have a voice in public. The Democratic candidate was not only black, but also overtly professorial, and this didn't diminish his popularity with the public. Hillary Clinton and, yes, even Sarah Palin normalised the idea of more female authority in politics. In a very short period of time, the unthinkable became the reality, and Maddow had her very own MSNBC programme.

Maddow's audience is still small, but she inspires devotion in her fans, because she doesn't fit the tedious mould of most political talkshow hosts. Maddow openly identifies with the wild world of the liberal blogosphere, and even went so far as to wear pajamas on her show to cheekily demonstrate solidarity with bloggers after Palin denounced the netroots.

Like bloggers, Maddow knows that the key to building rapport with your audience isn't making yourself into an aloof portrayal of authority, but to show your human side and sense of humour. To this end, Maddow lets her idiosyncrasies become known, such as her obsession with classic cocktails.

But what really endears her to American liberals is the way she takes her job and the authority it gives her seriously. Maddow is less interested in the shouting fests that dominate most cable news and instead favours in-depth interviews with experts who are permitted to show their expertise on air without being interrupted. Hers may be the only show on cable news were feminists come on air to speak their minds without being paired off with belligerent sexists who dominate the conversation by yelling over their points.

But Maddow isn't opposed to fair-mindedness. She often brings on conservatives for the same kind of in-depth interviews, and even when she strongly disagrees, she always gives them a chance to air their views (and generally hang themselves with those views). Her show is the exact opposite of Bill O'Reilly's show. Where he cuts people off for saying things he doesn't like, Maddow digs in deeper.

She also gives far more coverage to issues other hosts avoid because they're big downers. Maddow is the only reliable source of televised information on the growing problem of domestic terrorism in the US, and the only mainstream pundit to pay attention to the network of anti-abortion activists that quietly support the few that work up the courage to shoot doctors or bomb clinics. She doesn't treat the rapid growth of the extreme right in America like it's a joke or a minimal issue, as do other hosts, but as a serious threat to our democracy. In her transition to the mainstream media, the only thing Maddow seems to have given up is the thick-framed glasses she prefers to wear off-camera.

Unfortunately, the Maddow magic might not have much of a lifespan. During the US election, there was a hunger for televised liberal content, and no one does it better than Maddow. It seems that now, most liberals have turned off their TVs and returned to getting most information from the internet, and Maddow's ratings have plummeted as a result.

Video clips of her shows are routinely traded on liberal blogs, but that doesn't translate into ad revenue for MSNBC. Hopefully, the next round of US elections will push her ratings back up again, because we can't afford to lose the sole voice of intellectual liberalism in the cable news desert.